We plan to analyze the distribution of HRP labelled cells in the cortex of cats after HRP is injected into the pons. The aim of this experiment is to relate the position of filled cells in cortex to their position in the visual field. We will inject the entire monkey pons with horseradish peroxidase, and study the distribution of labelled cells in the cortex. We are especially interested in the extent to which extrastriate cortical areas show lablelled cells. Preliminary studies suggest that there may be two broad groups of extrastriate cortical areas, one of which projects to the pons, the other of which does not. One area may be involved in visual guidance of movement, the other in the identification of form and color. We plan also to study visuomotor performance in monkeys with lesions of the parietal, temporal, or frontal arcuate cortex. The aim of these experiments is to test the idea that loss of visually guided finger movements after posterior parietal lesion may be due to the interruption of a corticopontocerebellar pathway, rather than the destruction of a corticocortical circuit.